Peptide ChooserWhat an FDA warning letter means, and what it does not.
Short answer
A warning letter is the FDA's formal notice that it found what it believes are significant violations of the law; the company is asked to reply within 15 business days.1 It is public record, but it is not a court ruling and not a fine. Of the 172 letters on our letters page, the most common subject is "False & Misleading Claims/Misbranded" (59 letters).2
What is an FDA warning letter?
When the FDA finds what it believes are significant violations of federal rules, it tells the company, often in a warning letter. The letter names the problems, for example poor manufacturing practices, claims about what a product can do, or wrong directions for use.1
The company is asked to reply within a set time, with its plan to fix the problems or with its reasons if it disagrees.1 The FDA publishes the letters on fda.gov, sometimes with private details removed, so anyone can read them.
What do the letters to peptide sellers say?
Our letters page lists 172 FDA warning letters sent to peptide sellers, compounders and online clinics since 12 Jun 2023.2 Each has a subject, the FDA's short label for the problem. The most common ones:
- False & Misleading Claims/Misbranded: 59 letters
- Unlawful Sale of Unapproved and Misbranded Drugs to United States Consumers Over the Internet: 59 letters
- Unapproved New Drugs/Misbranded: 20 letters
- Compounding Pharmacy/Adulterated Drug Products: 11 letters
In plain words: misbranded means the label or the website says something the FDA believes is false or not allowed, such as claims a product cannot back up; unapproved new drug means a product sold as a medicine without FDA approval; adulterated and CGMP point to how a product was made, such as poor manufacturing practice.1 Subjects marked "(Telehealth)" went to online clinics.
Who gets warning letters?
Any company the FDA oversees can get one: drug makers, pharmacies, online clinics and shops. Of the 172 letters on our letters page, 109 went to telehealth companies and online clinics, 20 to research-use peptide shops and 11 to compounding pharmacies.2
Each letter is on fda.gov, where anyone can read it in full. It names the company, the products and the claims or practices the FDA objects to, and it says what the FDA expects the company to do.
What happens after a letter?
First the company replies. If it plans to fix the problems, the FDA checks the corrections, usually with a follow-up inspection.1
When the FDA has checked that the problems were really fixed, it may send a close-out letter. A promise to fix is not enough for one, and when a problem by its nature cannot be fixed, no close-out letter comes.1
If the FDA later finds the problems again, it may take further action without another warning.1
Why is a letter not a verdict?
A warning letter is the FDA's view at the time it was written. The company can answer with its own reasons and evidence, and what both sides do next can change where things stand.1 No court has ruled, and no fine comes with the letter itself.
After a letter, a company may fix the problem, change its website or stop selling the product. The letter keeps its date, so read it as what the FDA found at that time, and check the date before you judge a seller today.
So a letter is a fact worth knowing, not proof that a product is dangerous. And no letter is not proof of anything either: a shop without a letter has simply not been sent one.
How do we show letters?
On our letters page every letter is listed newest first, with its date, the company as the FDA names it, the subject, the FDA office that sent it and a link to the letter on fda.gov. When we can match a letter to a shop or clinic in our database, its name is shown under the company.
In the seller windows on our goal pages each shop has a chip with its number of FDA warning letters, and the "No FDA letter" check is one of its five checks. On the weight loss page each clinic shows the date of its newest letter. A shop or clinic with a letter is still listed: the letter is public record, and you can read it and decide.
What to do next
Sources
- FDA, About Warning and Close-Out Letters, current as of 20 Mar 2024: https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/about-warning-and-close-out-letters
- Peptide Chooser, FDA warning letters to peptide sellers, compounders and online clinics, checked 2 Nov 2026